Foreign Intelligence Surveillance Act

The Foreign Intelligence Surveillance Act of 1978 (FISA, , ) is a United States federal law that establishes procedures for the surveillance and collection of foreign intelligence on domestic soil.

FISA was enacted in response to revelations of widespread privacy violations by the federal government under president Richard Nixon. It requires federal law enforcement and intelligence agencies to obtain authorization for gathering "foreign intelligence information" between "foreign powers" and "agents of foreign powers" suspected of espionage or terrorism. The law established the Foreign Intelligence Surveillance Court (FISC) to oversee requests for surveillance warrants.

Although FISA was initially limited to government use of electronic surveillance, subsequent amendments have broadened the law to regulate other intelligence-gathering methods, including physical searches, pen register and trap and trace (PR/TT) devices, and compelling the production of certain types of business records.

FISA has been repeatedly amended since the September 11 attacks, with several added provisions garnering political and public controversy due to privacy concerns. Provided by Wikipedia